A quick walkthrough of podman's 2.1.x rootless networking: create a CNI network, attach two containers, and hit one from the other.
Install a mainline kernel on Ubuntu 20.04 via ubuntu-mainline-kernel.sh and sign it with your MOK key so Secure Boot keeps working.
Turn on Wayland fractional scaling on Ubuntu 20.04 and make Firefox and Thunderbird render natively instead of going through XWayland.